25503769649 has 2 divisors, whose sum is σ = 25503769650. Its totient is φ = 25503769648.

The previous prime is 25503769607. The next prime is 25503769661. The reversal of 25503769649 is 94696730552.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 23304159649 + 2199610000 = 152657^2 + 46900^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-25503769649 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 25503769594 and 25503769603.

It is not a weakly prime, because it can be changed into another prime (25503769549) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12751884824 + 12751884825.

It is an arithmetic number, because the mean of its divisors is an integer number (12751884825).

Almost surely, 2^25503769649 is an apocalyptic number.

It is an amenable number.

25503769649 is a deficient number, since it is larger than the sum of its proper divisors (1).

25503769649 is an equidigital number, since it uses as much as digits as its factorization.

25503769649 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 12247200, while the sum is 56.

The spelling of 25503769649 in words is "twenty-five billion, five hundred three million, seven hundred sixty-nine thousand, six hundred forty-nine".